1. Field of the Invention
The present invention relates to a blast processing method, and more specifically, to a blast processing method for removing a deposit adhered onto a component part of a semiconductor manufacturing apparatus.
2. Description of the Related Art
In usual, in manufacture of a semiconductor device, various films such as a silicon oxide film are formed on a wafer by using a semiconductor manufacturing apparatus.
In a step of generating the films, a deposition is sometimes adhered onto a heater, an electrostatic chuck, or a susceptor, which constructs the semiconductor manufacturing apparatus. When the deposition is adhered onto the heater or the susceptor, uniform heating performance for the wafer is decreased, and reproducibility of device characteristics or the like is reduced. Moreover, when the deposition is adhered onto the electrostatic chuck, sufficient electrostatic suction force is not generated, and surface roughness thereof or the like is changed to change a degree of contact of the electrostatic chuck with the wafer and a way of heat transfer therefrom to the wafer. Thus, the uniform heating performance for the wafer at a time of plasma heat input is decreased, and the reproducibility of the device characteristics or the like is reduced.
Therefore, process of periodically removing the deposit adhered onto such a component part of the semiconductor manufacturing apparatus has been heretofore performed (for example, refer to Japanese Patent Laid-Open Publication Nos. 2002-28599 and 2005-193308).
However, though a deposit removal method described in a related art of Japanese Patent Laid-Open Publication No. 2002-28599 is a method of blowing blasting beads to such a processing object, there has been an apprehension that the blasting beads may remain on the processing object, resulting in being a particulate contamination source.
Moreover, a deposit removal method disclosed in Japanese Patent Laid-Open Publication No. 2005-193308 is a method of blowing a blasting material to the processing object. However, since a pressure and the like at a time of blowing the blasting material are not regulated, there has been an apprehension that such a problem may occur that a surface of the processing object is damaged when the pressure is too large.